Jet vapor reduction of the thickness of process layers

ABSTRACT

The present invention is directed to a method and apparatus for reducing the thickness of a process layer. The method comprises generating a relatively high velocity gas stream comprised of active ions that will react with the process layer, and moving the wafer relative to the nozzle to effect a reduction in the thickness of the process layer. The apparatus is comprised of a process chamber, means for securing a wafer in the chamber, a nozzle having an exit that is substantially the same width as the diameter of the wafer positioned in the chamber. The apparatus further comprises a means for moving the wafer relative to the nozzle.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is generally directed to the field ofsemiconductor processing, and, more particularly, to reducing thethickness of previously-formed process layers.

2. Description of the Related Art

Within the semiconductor industry there is a constant drive to reducethe feature size of semiconductor devices, e.g., transistors. Reductionsin feature size may lead to increased performance of the device, i.e.,it may operate at greater speeds. Additionally, reducing the featuresize of the semiconductor devices may increase profitability, in that,all other things being equal, smaller feature sizes may result in morechips being manufactured on the same size substrate or wafer.

As feature sizes are reduced, e.g., as channel lengths are reduced, acorresponding reduction in size or scaling of other parts of thesemiconductor device may also be required. For example, in metal oxidefield effect transistors, the thickness of the gate insulation layer mayhave to be reduced to optimize the performance of the semiconductordevice. However, in forming a process layer, such as a gate insulationlayer, modern forming methods and devices may not be able to directlyform the process layers as thin as is desirable for the finishedsemiconductor device. Thus, there is a need for a method and apparatusthat may be used to reduce the thickness of the previously-formedprocess layers.

The present invention is directed to a semiconductor device that solvessome or all of the aforementioned problems and a method for making same.

SUMMARY OF THE INVENTION

The present invention is directed to a method and apparatus for reducingthe thickness of a process layer. The method is comprised of positioninga wafer in proximity to a nozzle, the wafer having a process layerpositioned thereon. The method further comprises generating a gas streamthrough the nozzle such that the stream exits the nozzle at a velocityranging from approximately 100-1200 feet per second, and moving thewafer, and accordingly the process layer, relative to the nozzle. Thegas stream is comprised of active ions that will react with the processlayer and thereby reduce the thickness of the process layer.

The apparatus is comprised of a process chamber, a means for securing awafer within the chamber, the wafer having a process layer positionedthereon. The apparatus further comprises a nozzle coupled to the processchamber, the nozzle has an exit that is substantially the same width asthe diameter of the wafer positioned in the process chamber. Theapparatus further includes a means for moving the wafer relative to thenozzle.

The apparatus further comprises a nozzle for use in reducing thethickness of a process layer positioned on a wafer. The nozzle iscomprised of a housing that is adapted for coupling to a processchamber, and at least one gas inlet in fluid communication with thenozzle. The nozzle further comprises an exit that is at leastsubstantially as wide as the diameter of the wafer.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be understood by reference to the followingdescription taken in conjunction with the accompanying drawings, inwhich like reference numerals identify like elements, and in which:

FIG. 1 is a cross-sectional, schematic view of an apparatus of thepresent invention;

FIG. 2 is a cross-sectional view of an illustrative circulating fluidsystem that may be used with the present invention;

FIG. 3 is a cross-sectional, schematic view of an illustrative nozzlethat may be used with the present invention;

FIG. 4 is a cross-sectional, schematic view of another illustrativenozzle that may be used with the present invention;

FIG. 5 is a cross-sectional side view of the nozzle shown in FIG. 4;

FIG. 6 is a cross-sectional view of an illustrative nozzle of thepresent invention having a generally rectangular cross-section; and

FIG. 7 is a cross-sectional view of an illustrative nozzle of thepresent invention having a generally oval cross-section.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof have been shown by wayof example in the drawings and are herein described in detail. It shouldbe understood, however, that the description herein of specificembodiments is not intended to limit the invention to the particularforms disclosed, but on the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

Illustrative embodiments of the invention are described below. In theinterest of clarity, not all features of an actual implementation aredescribed in this specification. It will of course be appreciated thatin the development of any such actual embodiment, numerousimplementation-specific decisions must be made to achieve thedevelopers' specific goals, such as compliance with system-related andbusiness-related constraints, which will vary from one implementation toanother. Moreover, it will be appreciated that such a development effortmight be complex and time-consuming, but would nevertheless be a routineundertaking for those of ordinary skill in the art having the benefit ofthis disclosure.

One embodiment of a jet vapor reduction apparatus 10 is shown in FIG. 1.The apparatus 10 may be comprised of a process chamber 12, a vacuum pump14, a nozzle 16, a diluting gas inlet 18, a removal gas inlet 20, amicrowave cavity 22, and a wafer chuck 24. The nozzle 16 may be any of avariety of configurations, as will become apparent upon a completereading of the entire specification. Illustrative embodiments of thenozzle 16 are disclosed more fully below. Additionally, although thediluting gas inlet 18 and removal gas inlet 20 are depicted as singlelines, those skilled in the art will recognize that the diluting gasinlet 18 and/or the removal gas inlet 20 may be comprised of multipleinlets. Moreover, separate inlet lines for the diluting gas and theremoval gas may not be used. Rather, the diluting gas (if used) and theremoval gas may be mixed together and then supplied to the nozzle 16 viaa single inlet line. Of course, other configurations may be possible forsupplying the removal gas and, if used, the diluting gas to the nozzle16. The location of the nozzle exit relative to a surface 29 of aprocess layer 25 may vary, and, in one embodiment, may vary fromapproximately 0.5-5.0 inches. Moreover, although the nozzle 16 isdepicted herein as being positioned approximately perpendicular to thesurface 29 of the process layer 25, the nozzle 16 may be positioned suchthat the gas exiting the nozzle impacts the surface 29 of the processlayer 25 at an angle.

As shown in FIG. 1, a wafer 26 may be positioned on the wafer chuck 24.The wafer 26 may be secured to the wafer chuck 24 by a variety of means,such as by a mechanical clamp or by a vacuum. As will be appreciated bythose skilled in the art, the wafer 26 may have a plurality of processlayers (not shown) formed above a surface 27 of the wafer 26. One suchillustrative process layer 25 is shown in FIG. 1. In general, the jetvapor reduction apparatus 10 may be used to reduce the thickness of theillustrative process layer 25 as the wafer 26 is passed under a streamof relatively high speed removal gas exiting from nozzle 16. The processis continued until the process layer 25 has been reduced to its desiredfinal thickness, as determined by, for example, an ellipsometer ortimer. The details of this process are discussed more fully below.

In one embodiment, the present invention may be practiced through use ofone of the devices employed in a traditional jet nitride depositionprocess. One such device is a jet vapor deposition apparatus sold by JetVapor Deposition Company under the model number JVD-100. In general, thepresent invention may be practiced using that apparatus with appropriatechanges to various process parameters, such as the gas injected into theprocess chamber 12, the speed of movement of the wafer, etc., as will bemore fully described below. The present invention may also be practicedin a jet vapor reduction apparatus 10 employing a novel design for thenozzle 16, as will be described more fully below.

In operation, the wafer 26 is secured to the wafer chuck 24. Thereafter,the vacuum pump 14 is used to establish a vacuum in the process chamber12. In one embodiment, a vacuum of approximately 10⁻⁷ Torr isestablished in the process chamber 12. Thereafter, a removal gas may beintroduced into the process chamber 12 via the removal gas inlet 20 andthe nozzle 16. The gas selected as the removal gas will vary dependingupon, for example, the composition of the process layer 25 to be reducedby the present process. The removal gas should contain an active ionthat will react with the process layer 27 to thereby reduce thethickness of the process layer 25.

For example, if the previously-formed process layer 25 is comprised ofsilicon nitride (SiN₃), the removal gas may be comprised of hydrogenfluorine (HF) or nitrogen fluoride (NF₃). The active fluorine ions reactwith the silicon nitride process layer to form silicon hexafluoride(SiF₆), thereby reducing the thickness of the deposited layer of siliconnitride. The present invention may also be used to reduce the thicknessof previously-deposited layers of metal. For example, if thepreviously-formed process layer 25 is comprised of, for example,aluminum (Al), the removal gas may be comprised of, for example,chlorine (Cl₂). The active chlorine ions will react with the aluminumprocess layer to form aluminum chloride (AlCl₂) which will reduce thethickness of the previously-formed layer of aluminum. Thus, as will bereadily appreciated to those skilled in the art, the novel methoddisclosed herein may be used to reduce the thickness of the processlayers 25 formed from a vast variety of materials.

In one embodiment, the removal gas may be supplied to the nozzle 16 at apressure of approximately 60-80 psi and at approximately ambienttemperature. The exact process parameters for the removal gas arematters of design choice that may vary depending upon the particularapplication. Although not required, the removal gas may be combined witha diluting gas, for example, nitrogen (N₂) or argon (Ar), that isintroduced into the process chamber 12 via the diluting gas inlet 18 andthe nozzle 16. The removal gas, e.g., HF, NF₃ or Cl₂, may be diluted toresult in a concentration that may range from 100:1 to 1000:1. Thedilution of the removal gas, if any, may be varied as a matter of designchoice or as required by a particular application. In general, all otherthings being equal, the more the removal gas is diluted, the slower theremoval rate of the process layer 25. Conversely, the more concentratedthe removal gas, the faster the removal rate of the process layer 25. Ofcourse, the concentration of the removal gas may be varied throughoutany particular process, e.g, a higher concentration of removal gas maybe used to obtain initially high removal rates followed by a lowerconcentration for a slower removal rate.

The combined flow rate of the removal gas and the diluting gas may rangefrom approximately 0.5-2 liters per minute. The nozzle 16 is designedand configured such that the velocity of the gas stream exiting thenozzle 16 is at a speed ranging from approximately 100 ft/sec tosupersonic speeds, e.g., speeds above approximately 1120. In oneillustrative embodiment, the gas flow rates and the design of the nozzle16 are such that the velocity of the gas stream as it exits the nozzle16 is somewhat below the supersonic range, for example, the exitvelocity may range from approximately 400-1000 ft/sec. Of course, theexact speed that the gas stream exits the nozzle 16 is a matter ofdesign choice that may be varied depending upon the particularapplication under consideration. In general, all other things beingequal, the greater the exit velocity of the gas stream, the faster theremoval rate of the illustrative process layer 25. Conversely, theslower the velocity of the gas stream, the slower the removal rate ofthe illustrative process layer 25.

A microwave generator (not shown) and the associated microwave cavity 22may be used to generate a plasma field that may be useful, inappropriate circumstances, to free the active ions in the removal gas.For example, if nitrogen fluoride (NH₃) is used as the removal gas, ahigh energy plasma may be required to break the fluoride away from thenitrogen. A standard microwave generator may be used to generate anenergy field of approximately 10-15000 watts to generate the plasma usedto disassociate the fluoride from the nitrogen. However, the microwavecavity 22 and associated microwave generator (not shown) may not berequired on all applications using the jet vapor reduction apparatus 10.For example, if hydrogen fluoride (HF) is used as the removal gas, thenthe microwave cavity 22 and microwave generator may not be required.

Although not required, a means may be provided to heat and/or cool theprocess layer 25 before or during the reducing process. The temperatureto which the process layer 25 is heated or cooled is a matter of designchoice and the desired rate of removal of the process layer 25. In1general, the higher the temperature of the process layer 25, the fasterthe removal rate of the process layer 25. Conversely, the lower thetemperature of the process layer 25, the slower the removal rate of theprocess layer 25. In one embodiment, the temperature of the processlayer 25 may be varied between approximately 10-200° C. Of course, as isreadily apparent to those skilled in the art, the temperature of theprocess layer 25 may be varied throughout the reduction process. Forexample, in an initial pass, the temperature of the process layer 25 maybe maintained at a relatively high temperature to increase the rate atwhich the illustrative process layer 25 is removed. Thereafter, thetemperature of the process layer 25 may be regulated to a relatively lowtemperature, e.g., ambient temperature, to slow the rate of removal ofthe illustrative process layer 25. Such a technique may allow rapidremoval of the bulk of the portion of the process layer 25 to beremoved, yet still allow for a final removal pass at a morecontrollable, slower removal rate to obtain the final desired thicknessof the process layer 25. Of course, the removal of the process layer 25does not have to be accomplished in multiple passes, it may beaccomplished in a single pass under an appropriately configured nozzle16.

In one illustrative embodiment, the heating/cooling of the process layer25 may be accomplished by having a circulating fluid system 30 that maybe embedded in, or attached to the wafer chuck 24. As shown in FIG. 2,the circulating fluid system 30 may have a fluid inlet 32 and a fluidoutlet 34. To cool the process layer 25, a cooling fluid, such as achilled glycol solution, may be circulated through the circulating fluidsystem 30 at a rate and temperature sufficient to cause the processlayer 25 to reach the desired temperature. Similarly, to heat theprocess layer 25, a hot fluid may be circulated through the circulatingfluid system 30. The details of construction of the circulating fluidsystem 30 are matters of design choice. For example, the circulatingfluid system 30 may be comprised of a cavity 36 and a plurality ofbaffles 38 formed in the wafer chuck 24. Alternatively, the baffles 38could be omitted resulting in a cavity 36 in the wafer chuck 24 throughwhich the heating/cooling fluid could be circulated. Of course, thecirculating fluid system 30 described herein is only one illustrativeexample of a means that may be used to heat or cool the process layer25. For example, an electrical grid or wire (not shown) embedded orcoupled to the wafer chuck 24 could be used to heat the process layer 25by resistance heating.

As generally described above, the jet vapor reduction apparatus 10 isdesigned such that the wafer 26, and therefore the process layer 25, maybe passed under the nozzle 16 as a gas comprised of active ions isexiting the nozzle 16 at a relatively high speed. The exact means thatis used to move the wafer 26 relative to the nozzle 16 is a matter ofdesign choice. In one embodiment, the wafer transport mechanism used ina traditional jet vapor nitride deposition system, such as the Model No.JVD-100, sold by Jet Vapor Deposition Company (not shown), may be usedto move the wafer 26 relative to the nozzle 16. Of course, any otherautomated or robotic mechanism for moving the wafer 26 may beacceptable. Whatever mechanism is selected to move the wafer 26, thewafer 26 should normally move at a rate of between approximately 10-200ft/min relative to the nozzle 16. In general, increasing the rate atwhich the process layer 25 is moved under the jet nozzle 16 willdecrease the amount of process layer 25 removed by the process.Conversely, the slower the process layer 25 is moved under the nozzle16, the greater the amount of the process layer 25 removed by theprocess. Thus, for removing large amounts of an initially thick processlayer 25, the wafer speed relative to the nozzle 16 should be relativelyslow. Conversely, to remove a very thin portion of a process layer 25,e.g., when forming a very thin gate insulation layer, it may bedesirable to move the process layer 25 as fast as possible under thenozzle 16. Current jet nitride deposition systems employ wafer transportsystems using stepper motors, thus, the speed of the wafer movementwithin these systems is at the lower end of the above range. In order toachieve the upper end of the above range, a system comprised of servomotors and feedback control would be required. As is readily apparent tothose skilled in the art, the movement of the wafer 26 as compared tothe nozzle 16 is relative movement. That is, the nozzle 16 could bemoved relative to a stationary wafer 26.

As stated previously, the present invention may be used to reduce thethickness of a variety of process layers, irrespective of where or howthey are formed. The present invention may be practiced in a separatepiece of processing equipment, whose use is directed solely to the jetvapor reduction process disclosed herein, or, alternatively, the presentmethod may be practiced in an existing process apparatus. For example,after a layer of silicon nitride has been formed in a jet vapordeposition apparatus, the thickness of the deposited layer of siliconnitride may be reduced using the same apparatus used in the jet vapordeposition process. Of course, the appropriate gas connections wouldhave to be made to establish the flow of removal gas and diluting gas,and, if desired, the flow of cooling/heating fluid to the fluidcirculating system 30 would be started.

In one illustrative example using an existing jet vapor depositionapparatus, such as the Model No. JVD-100 referenced above (not shown),the nozzle 16 would be a co-axial dual-nozzle jet as shown in FIG. 3.Nozzle 16 is comprised of removal gas inlet 40, diluting gas inlet 42,and a plurality of valves 44, 46. Nozzle 16 is in fluid communicationwith the process chamber 12. The wafer 26 is positioned on wafer chuck24. The nozzle 16 is comprised of an inner tube 50 and an outer tuber52. In one illustrative embodiment, the diameter of outer tube 52 isapproximately 6 mm, while the diameter of inner tube 50 is approximately3 mm. This nozzle configuration would result in a gas stream that mayvary between 3-10 mm in diameter. If the present invention is employedin this type of existing jet vapor deposition apparatus, then it will benecessary to raster scan the process layer 25 relative to the nozzle 16.As will be readily apparent to those skilled in the art, in doing so, itwill be necessary to slightly overlap exiting passes, for example, byapproximately 10%, such that complete removal of the desired amount ofthe process layer 25 is insured. Using this technique and apparatus, thewafer 26 will be raster scanned underneath the nozzle 16 until thedesired amount of the process layer 25 is removed.

An alternative embodiment of a nozzle 16 that may be used with thepresent invention is shown in FIGS. 4 and 5. As shown therein, a wafer26, having a process layer 25 formed thereon, is positioned on a waferchuck 24 within process chamber 12. As shown in the drawings, the nozzle16 is comprised of a housing 79 comprised of, for example, a pluralityof sidewalls 39, 41. Of course, the sidewalls 39, 41 of the nozzle 16may be constructed so as to diverge or converge with respect to oneanother. Additionally, the nozzle 16 may be positioned such that gasexiting the nozzle 16 impacts the surface 29 at something other than thesubstantially perpendicular angle depicted in FIGS. 4 and 5. The nozzle16 is sized such that it is at least substantially the same width as theprocess layer 25 to be removed. The width of the nozzle 16 may be suchthat it is slightly greater than the diameter of the wafer 26 and, thus,the process layer 25. Of course, if desired, the nozzle configurationdepicted in FIGS. 4 and 5 may have a width that is somewhat less thanthe diameter of the wafer 26, e.g., 85% of the diameter of the wafer 26.Through use of a nozzle 16 having a width that is at least substantiallyas wide as the wafer 26 and, thus, the process layer 25, the thicknessof a process layer 25 may be reduced without having to raster scan theprocess layer 25 relative to the nozzle 16. Of course, with the nozzleconfiguration depicted in FIGS. 4 and 5, one or more passes may be usedto achieve the final desired thickness of the process layer 25.

The nozzle 16 should be designed such that there is uniform distributionof the removal gas and, if used, the diluting gas as the gas streamexits the nozzle 16. In one embodiment, this may be achieved though useof a removal gas header 60, a plurality of removal gas outlets 62, aremoval gas inlet 64, and a valve 66. The nozzle 16 may further be influid communication with a diluting gas header 68, a plurality ofdiluting gas outlets 70, a diluting gas inlet 72, and a valve 74. Theremoval gas outlets 62 and diluting gas outlets 70 may penetrate aflange 76. The precise number, size, configuration and location of theremoval gas outlets 62 and diluting gas inlets 72 are matters of designchoice and may vary depending upon a variety of process parameters, suchas the type, pressure flow rate and temperature of the removal gas anddiluting gas used, the material and thickness of the process layer 25 tobe removed, the desired rate at which material is removed from theprocess layer 25, etc. In general, the nozzle 16 should be designed suchthat there is uniform flow of the removal gas and, if used, dilutinggas.

As shown in FIG. 6, the outlet 75 of the nozzle 16 may have a generallyrectangular configuration. In one illustrative embodiment, designed foruse with wafers approximately 8" in diameter, the outlet 75 of thenozzle 16 may be approximately 10 inches wide and 3 inches in length. Ofcourse, the outlet 75 of the nozzle 16 could be of any desired size.Alternatively, the outlet 75 of nozzle 16 could have a generally ovalconfiguration as shown in FIG. 7. Irrespective of the size andconfiguration of the nozzle 16, it is desirable that the nozzle be atleast substantially the same width, or slightly greater than the widthof the wafer 26 on which semiconductor devices are to be made. Thusconfigured, a process layer 25 formed above the entire surface of thewafer 26 may be removed, if desired, in a single pass or in multiplepasses without the need for raster scanning the nozzle 16 relative tothe wafer. Of course, the width of the nozzle 16 may vary depending onthe size of the wafer that will be subjected to the present process,e.g., if larger wafers are used, the width of the outlet 75 of thenozzle 16 may also be increased. For example, for 12" diameter wafers,the outlet 75 of the nozzle 16 may be approximately 14 inches wide.

As will be readily apparent to those skilled in the art, the presentinvention may be used to reduce the thickness of a variety ofpreviously-formed layers used in making semiconductor devices, e.g.,oxide layers, metal layers, nitride layers, polysilicon layers, glasslayers, etc. Moreover, the present invention may be employed as astand-alone process through which wafers will be processed on a batch orwafer basis. Alternatively, the present process may be employed as alater process step in existing processing equipment, e.g., jet vapornitride deposition followed by the reduction of the thickness of thedeposited nitride layer without removing the wafer from the processchamber.

The particular embodiments disclosed above are illustrative only, as theinvention may be modified and practiced in different but equivalentmanners apparent to those skilled in the art having the benefit of theteachings herein. Furthermore, no limitations are intended to thedetails of construction or design herein shown, other than as describedin the claims below. It is therefore evident that the particularembodiments disclosed above may be altered or modified and all suchvariations are considered within the scope and spirit of the invention.Accordingly, the protection sought herein is as set forth in the claimsbelow.

What is claimed:
 1. A method for reducing the thickness of a processlayer, comprising:positioning a wafer in proximity to a nozzle, saidwafer having a process layer positioned on said wafer; generating a gasstream through said nozzle that exits said nozzle at a speed rangingfrom approximately 100-1200 feet per second, said gas stream comprisedof active ions that will react with said process layer to form a gas;and moving said wafer relative to said nozzle.
 2. The method of claim 1,wherein said step of generating a gas stream comprises combining aremoval gas with a diluting gas.
 3. The method of claim 1, furthercomprising generating a plasma field and passing at least a portion ofsaid gas stream through said plasma field.
 4. The method of claim 1,wherein moving said wafer relative to said nozzle comprises rasterscanning said nozzle relative to said wafer.
 5. The method of claim 1,further comprising reducing the thickness of the entirety of saidprocess layer in a single pass as said wafer is moved relative to saidnozzle.
 6. The method of claim 1, wherein moving said wafer relative tosaid nozzle comprises actuating at least one electric motor.
 7. Themethod of claim 1, wherein generating a gas stream through said nozzlecomprises supplying a gas stream at approximately 60-80 pounds persquare inch.
 8. The method of claim 2, wherein combining a removal gaswith a diluting gas comprises combining a removal gas with a dilutinggas to result in a concentration of diluting gas relative to saidremoval gas of approximately 100:1 to 1000:1.
 9. The method of claim 1,wherein moving said wafer relative to said nozzle comprises moving saidwafer at a speed of approximately 10-200 feet per second relative tosaid nozzle.
 10. The method of claim 1, wherein said process layer iscomprised of silicon nitride and generating said gas stream is comprisedof generating a gas stream comprised of active fluorine ions.
 11. Themethod of claim 1, further comprising controlling the temperature ofsaid process layer.
 12. The method of claim 1, wherein said processlayer is comprised of aluminum and generating said gas stream iscomprised of generating a gas stream comprised of active chlorine ions.13. The method of claim 2, wherein said process layer is comprised ofsilicon nitride and combining said removal gas with a diluting gascomprises combining hydrogen fluorine or nitrogen fluoride with nitrogenor argon.
 14. A method for reducing the thickness of a process layer,comprising:positioning a wafer in proximity to a nozzle, said waferhaving a process layer positioned on said wafer; generating a gas streamthrough said nozzle that exits said nozzle at a speed ranging fromapproximately 100-1200 feet per second, said gas stream comprised ofactive ions that will react with said process layer to form a gas; andmoving said wafer at a speed of approximately 10-200 feet per secondrelative to said nozzle.
 15. The method of claim 14, wherein said stepof generating a gas stream comprises combining a removal gas with adiluting gas.
 16. The method of claim 14, further comprising generatinga plasma field and passing at least a portion of said gas stream throughsaid plasma field.
 17. The method of claim 14, wherein moving said waferrelative to said nozzle comprises raster scanning said nozzle relativeto said wafer.
 18. The method of claim 14, further comprising reducingthe thickness of the entirety of said process layer in a single pass assaid wafer is moved relative to said nozzle.
 19. The method of claim 14,wherein generating a gas stream through said nozzle comprises supplyinga gas stream at approximately 60-80 pounds per square inch.
 20. Themethod of claim 15, wherein combining a removal gas with a diluting gascomprises combining a removal gas with a diluting gas to result in aconcentration of diluting gas relative to said removal gas ofapproximately 100:1 to 1000:1.
 21. The method of claim 14, wherein saidprocess layer is comprised of silicon nitride and generating said gasstream is comprised of generating a gas stream comprised of activefluorine ions.
 22. The method of claim 14, wherein said process layer iscomprised of aluminum and generating said gas stream is comprised ofgenerating a gas stream comprised of active chlorine ions.
 23. Themethod of claim 15, wherein said process layer is comprised of siliconnitride and combining said removal gas with a diluting gas comprisescombining hydrogen fluorine or nitrogen fluoride with nitrogen or argon.24. The method of claim 14, further comprising controlling thetemperature of said process layer.
 25. A method for reducing thethickness of a layer of silicon nitride, comprising:positioning a waferin proximity to a nozzle, said wafer having a layer of silicon nitridepositioned on said wafer; generating a gas stream through said nozzle ata speed ranging from approximately 100-1200 feet per second, said gasstream comprised of active fluorine ions that will react with saidsilicon nitride layer; and moving said wafer relative to said nozzle.26. The method of claim 25, wherein generating said gas stream comprisesgenerating a gas stream comprised of hydrogen fluorine or nitrogenfluorine.
 27. The method of claim 25, wherein generating said gas streamcomprises generating a gas stream comprised of active fluorine ions anda diluting gas.
 28. The method of claim 25, further comprisinggenerating a plasma field and passing at least a portion of said gasstream through said plasma field.
 29. The method of claim 25, whereinmoving said wafer relative to said nozzle comprises raster scanning saidnozzle relative to said wafer.
 30. The method of claim 25, furthercomprising reducing the thickness of the entirety of said process layerin a single pass as said wafer is moved relative to said nozzle.
 31. Themethod of claim 25, wherein generating a gas stream through said nozzlecomprises supplying a gas stream at approximately 60-80 pounds persquare inch.
 32. The method of claim 25, wherein combining a removal gaswith a diluting gas comprises combining a removal gas with a dilutinggas to result in a concentration of diluting gas relative to saidremoval gas of approximately 100:1 to 1000:1.
 33. The method of claim25, further comprising controlling the temperature of said processlayer.